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exploration of Mackenzie River

...fur traders pushed westward across Canada in the late 18th century to the headwaters of rivers that flowed into Hudson Bay, seeking to tap the fur resources in the lands beyond. In 1778 one of them,
Peter Pond, found Portage La Loche (Methy Portage) connecting the headwaters of Churchill River with the Clearwater River, itself one of the east-bank tributaries of the Athabasca River. In 1789...